Single Pair Telephone and Data Line Protection.
The STC-TEL Series provides surge protection for single pair telephone and data lines using an advanced two-stage hybrid design. Silicon breakover devices protect equipment from overvoltage transients, while sneak and fault currents are mitigated with solid-state resettable fuses (PTCs). These units use two screw terminals to connect a Telco line to the protector. The equipment to be protected then plugs into a standard female modular jack.
STC-TEL Series RJ Connection Surge Protective Devices Catalog Pages